Remote control arrow buttons suddenly dont select things anymore

To change the language on your Panasonic CN-H500D, press the "Menu" button on the remote control. Use the arrow keys to select the "Setup" option, then press the "Enter" button. Select the "Language" option, then press the "Enter" button. Use the arrow keys to select the language you want to use, then press the "Enter" button. The language will now be changed to the one you selected.

with regard to using the remote control :

Make sure the batteries in the remote are working (they go in the back of the remote at the bottom).

Turn on the DVD player with the power button on the DP300 itself (lower left). Open the dvd tray either with the remote (press open/close button, upper right) or with the button on the DP300. Put a DVD in the tray and close it with the remote or the button on the DP300. The DVD should load.

Use the arrow buttons in the centre of the remote to select choices from the onscreen menu of the DVD. Press Play (centre of the 4 arrow buttons) to activate the choice you want. For example, if you want to play a movie, use the arrow buttons to go up or down until "play movie" is selected, then hit PLAY, and movie will play. If you want to choose a scene/chapter of the movie, use arrow buttons to go up or down until Scene Selection or Chapter is selected (highlighted), and press PLAY. This should bring up a list of the scenes or chapters. Use the arrow buttons to select the one you want, then hit PLAY, and that scene should play.

If the DVD tray is taking less than 20 seconds to operate, there is likely no problem. If it is taking more, there may be. I think the mechanism that opens and closes the tray is often the first thing to stop working on DVD and CD players.

Universal remote may give you few controls like power on-off, FF, REW etc but Menu may not open.
Substitute remote for this Combo is available in Remotes.com and original remote is available in Panasonic Parts under part number LSSQ0374
Same thing goes to your Sharp tv.
Thanks.

Use the remote control and press the MENU button and select the OPTION with the UP and DOWN arrow buttons. Press ENTER button and then press UP and DOWN arrow button to select CONTROL PANEL use LEFT and RIGHT arrow button to VALID the control panel buttons

If you have a loss of the remote control while the control panel is invalidated.

Press and hold the MENU button for 2 seconds with pressing the ENTER button to enter the MENU and VALID the control panel.

I found my misplaced Manual
Thank You
Pat Chatelier

NEED REPLACED DVD MECHANISM UNIT
Manufacturer Panasonic Part Number LSXK0118 Description MECHANISM

I found a newer Comcast PDF file that shows a 5 digit number for tv with vcr ( no mention of DVD) but the code worked to turn on the tv and cable box together. My problem is it won't work the volume, yet
https://www.comcast.com/MediaLibrary/1/1/Customers/Customer_Support/Digital_Cable_with_OD/Digital_Cable/remotes/Remote_M1067BX3.pdf

1. Press the Menu button on your remote control 2. Press the 5 button on your remote control 
3. Press the 7 button on your remote control 
4. Press the 5 button on your remote control 
5. Press the 3 button on your remote control 
6. Press the 8 button on your remote control 
7. The currently selected region will be indicated on the TV. 
8. Press the 1 button on your remote control for region 1, the 2 button for region 2, and so on, or the 9 button for multi-region playback 
9. Press the Menu button on your remote control 
10. Press the Menu button on your remote control 

Tested with Region 1 DVD's on my UK player (Region 2 bought from Comet)

You need to program the VCR (which turns the sey on/off) as an aux, then program any Panasonic TV type for TV, and then set the STB button to control STB, TV and AUX and you should be set.

This unit has seperate power supplies for the DVD and VCR side and the DVD side supply seems prone to failure. I have not isolated the cause, but can tell you this will require a component level repair. Unless you are a tech you may as well buy a new unit.